🥅 Test for NULL bytes before sending string args - #712
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We were missing any basic tests for sending UTF-8 strings!
Also dropped some redundant comments
These are identical regexps, make the code better self-documenting. Note that ASTRING_SPECIALS is identical to ResponseParser::Patterns::ASTRING_SPECIALS.
This allows us to raise the exception during argument validation, rather than waiting until we are sending the command (which is too late to save the connection from being corrupted).
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| UNQUOTABLE_CHARS = /\r\n/n |
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This bug was introduced by a742a10. When I extracted the `UNQUOTABLE_CHARS` regexp into a constant, I didn't copied it exactly. It was converted from a character class into a sequence of bytes: ```ruby # It should've been this: UNQUOTABLE_CHARS = /[\0\r\n]/n # But I incorrectly copied it as this: UNQUOTABLE_CHARS = /\0\r\n/n ``` If that regexp were the only guard, this regexp would've allowed CRLF injections! Fortunately, quoted strings are now sent using `Net::IMAP::QuotedString` (since #698, released in v0.6.4.1), and that _does_ correctly validate that the input is a valid quoted string. So, the string isn't _sent_ as invalid quoted data. Unfortunately, this does result in an exception for strings that could be valid literals. And, because it crashes while sending command arguments, rather than during validation, the connection will be broken.
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The latest release does validate that atoms, quoted strings, literals don't contain any NULL bytes. However generic string arguments would not be fully validated until they attempted to send (inside
#send_string_data).This change allows us to raise the exception during argument validation, rather than waiting until we are sending the command (which is too late to save the connection from being broken).
Additionally:
send_string_data.astring(used for generic string args) andAtom. This (or something like it) may be promoted to public rdoc in a future version.